Olson Time Zone Database to Standard Windows Time Zone v0.1

3/09/2008

Hi All,

Recently, I have been playing around with some code from the Olson Time Zone Database and OpenID. The biggest problem I have found is that the Olson Time Zone Database doesn’t provide a Windows Standard Format Conversion in their database – so I set about doing this myself. I am by no means guaranteeing that this is 100% perfect – hence the reason I am releasing it on the web for all to assist in improving it. Basically, it converts the Olson Time Zone Database to the Windows Standard Format Time Zone for easy use with OpenID and websites. The *.xlsx and *.xls are available by clicking on each.

It’s taken a bit of Time (*pardon the pun*) – but I have come up with a pretty complete offering that I am publishing under an ISC Licence.

The detail of such a license are available in the file and below. Basically, your free to do with it as you want – although I would hope that any modifications, improvements and the like you make – you can send back to me so I can update this post for the benefit of everyone else.

Permission to use, copy, modify, and/or distribute this software for any
purpose with or without fee is hereby granted, provided that the above
copyright notice and this permission notice appear in all copies.

THE SOFTWARE IS PROVIDED “AS IS” AND THE AUTHOR DISCLAIMS ALL WARRANTIES
WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

tim@timdavis.com.au

Dan

I think I found a few additions when parsing data from geoname.org.

Europe/Sarajevo,Central European Standard Time
Europe/Guernsey,GMT Standard Time
Europe/Zagreb,Central European Standard Time
Europe/Isle_of_Man,GMT Standard Time
Asia/Calcutta,India Standard Time
Europe/Jersey,GMT Standard Time
Europe/Podgorica,Central European Standard Time
Europe/Skopje,Central European Standard Time
Europe/Ljubljana,Central European Standard Time
Arctic/Longyearbyen,Central European Standard Time
Europe/Bratislava,Central European Standard Time
Europe/San_Marino,Central European Standard Time
America/Shiprock,Mountain Standard Time
Asia/Saigon,SE Asia Standard Time

Thanks for the data!

Dan

Chris

There are some errors on the combined excel sheet with the ETC time zones. All the Etc/GMT signs are opposite what they should be as shown in the display_name column

Brett

Chris, sign reversal is not an error, but an artifact of the way the Olson timezone database names these timezones in accordance with the POSIX standard. The following comment is in the db:

# We use POSIX-style signs in the Zone names and the output abbreviations,
# even though this is the opposite of what many people expect.
# POSIX has positive signs west of Greenwich, but many people expect
# positive signs east of Greenwich. For example, TZ=’Etc/GMT+4′ uses
# the abbreviation “GMT+4″ and corresponds to 4 hours behind UTC
# (i.e. west of Greenwich) even though many people would expect it to
# mean 4 hours ahead of UTC (i.e. east of Greenwich).

A good piece of work. Saves me a chunk of Time! All I have to do now is re-jig in javascript.

Not your fault, but I find it curious that Beijing is shown in Olson only as a comment attached to Shanghai. I’d have thought the capital of the world’s largest (?) and most populous country would merit its own entry.

In addition, Beijing is variously shown as CCT (China Coastal Time) rather than CST (China Standard Time). Same time throughout China.

John PERRY

PS you have CAT down as South Africa Standard Time when it should be Central Africa Time.

mikeJ

This is a very useful table. Thanks! Would be great if you put out a v0.2 with the extra info from the comments. Some official body really should table this over.

mikeJ

I filled in the details from the info that Dan added above:

426,Europe/Sarajevo,Bosnia and Herzegovina,-,3600,CEST,Central European Standard Time
427,Europe/Guernsey,Guernsey,-,0,GMT,GMT Standard Time
428,Europe/Zagreb,Croatia,-,3600,CEST,Central European Standard Time
429,Europe/Isle_of_Man,Isle of Man,-,0,GMT,GMT Standard Time
430,Asia/Calcutta,India,-,19800,IST,India Standard Time
431,Europe/Jersey,Jersey,-,0,GMT,GMT Standard Time
432,Europe/Podgorica,Montenegro,-,3600,CEST,Central European Standard Time
433,Europe/Skopje,Macedonia,-,3600,CEST,Central European Standard Time
434,Europe/Ljubljana,Slovenia,-,3600,CEST,Central
European Standard Time
435,Arctic/Longyearbyen,Norway,-,3600,CEST,Central European Standard Time
436,Europe/Bratislava,Slovakia,-,3600,CEST,Central European Standard Time
437,Europe/San_Marino,San Marino,-,3600,CEST,Central European Standard Time
438,America/Shiprock,US,-,-25200,MST,Mountain Standard Time
439,Asia/Saigon,Vietnam,-,25200,ICT,SE Asia Standard Time

Kronuz

Nice work… I found some missing timezones in the list (I think Asia/Kathmandu is actually not missing, but misspelled):

Antarctica/South_Pole,New Zealand Standard Time
America/Argentina/Salta,Argentina Standard Time
Europe/Mariehamn,Eastern European Standard Time
America/St_Barthelemy,Atlantic Standard Time
America/Santarem,Brasilia Time
Europe/Zagreb,Central European Standard Time
America/Marigot,Atlantic Standard Time
Europe/Vatican,Central European Standard Time
Asia/Kathmandu,Nepal Standard Time

I also wonder what’s the difference between some timezones in the Windows standard name, such as “Central European Standard Time” vs “Central Europe Standard Time”… does anyone know why there are both names? which one is the correct one?

Nesken

Excellent work! thank you.

yury

Thanks for the great resource. A little change is needed:
“Asia/Jerusalem” should map to “Israel Standard Time” instead of “Middle East Standard Time”